linux-kernel - [PATCH v3 0/2] pci: endpoint: Fix double free in pci_epf

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 27 Feb 2018 11:02:28 +0100
From:   Rolf Evers-Fischer <embedded24@...rs-fischer.de>
To:     kishon@...com
Cc:     lorenzo.pieralisi@....com, bhelgaas@...gle.com,
        linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
        andy.shevchenko@...il.com,
        Rolf Evers-Fischer <embedded24@...rs-fischer.de>
Subject: [PATCH v3 0/2] pci: endpoint: Fix double free in pci_epf_create()

This is version 3 of a patchset to avoid double free in function
'pci_epf_create()'.

When I accidentally created a new endpoint device with an empty name,
the kernel warned about "attempted to be registered with empty name!"
and crashed afterwards.

It turned out that the crash was not caused by the 'device_add()'
function itself, but by a double kfree of 'epf->name' and 'epf'.

The first patch just simplifies the code, while the second patch
fixes the problem.

Changes in v3:
- Matched to other pending pci endpoint commits (thanks, Bjorn!)
- Added "Fixes" tag in patch 2 (thanks, Andy!)

Changes in v2:
- Based on feedback from Lorenzo, Andy and Kishon (thanks!)
- Change IDs removed
- First patch completely reworked in order to eliminate the
  need for the second 'kstrdup' allocation and the 'kfree' of
  the first allocation.
  It was tested with name="pci_epf_test.0" and name="pci_epb":
  The 'epf->name' was "pci_epf_test" or "pci_epb" (=unchanged).

Rolf Evers-Fischer (2):
  pci: endpoint: Simplify name allocation for epf device
  pci: endpoint: Fix kernel panic after put_device()

 drivers/pci/endpoint/pci-epf-core.c | 24 +++++-------------------
 1 file changed, 5 insertions(+), 19 deletions(-)

-- 
2.16.2